Combined bagging and packaging machine



Jan. 23, 1968 H. c. HOUSE COMBINED BAGGING AND PACKAGING MACHINE 5Sheets-Sheet 1 Filed Feb. 24, 1964 FIG.

INVENTOR ATTORNEY Jan. 23, 1968 H. c. HOUSE 3,364,659

COMBINED BAGGING AND PACKAGING MACHINE Filed Feb. 24. 1964 5Sheets-Sheet n INVENTOR HAP! R! C HOUS E BY WI ATTORNEY H. C. HOUSE Jan.23, 1968 COMBINED BAGGING AND PACKAGING MACHINE 5 Sheets-Sheet FiledFeb. 24, 1964 INVENTOR HARRY C.HOUSE ATTORNEY Jan. 23, 1968 H. C. HOUSE3,364,650

COMBINED BAGGING AND PACKAGING MACHINE Filed Feb. 24, 1964 5 SheetsSheet4 FIG.5

INVENTOR 52 HARRY C.HOUSE ATTORNEY Jan. 23, 1968 H. c. HOUSE COMBINEDBAGGING AND PACKAGING MACHINE 5 Sheets-Sheet Filed Feb. 24, 1964 M W a1.. w! m N. x. V S viTW PM F g W A W s |l M ./5 T W a W W F G H i a W PFEG. I3

w W M n M c a 2 ':/S i

a W gr m E \E 1 E H A R R Y C- H O' U S E TTORNEY United States Patent()fifice assent Patented Jan. 23, 1968 3,364,650 CGMBINED BAGQING ANDPACKAGING MACHINE This invention relates to combined bagging andpackaging machines, and more particularly to such machines wherein thebag or finished package is produced from a continuous length of athermoplastic material in surrounding relationship with respect to thearticle to be packaged. Thus, fabrication of the bag and the packagingof the goods therein is accomplished in a single operation.

Desirably the machine or apparatus is automatic in operation and isreadily adjustable for severing bags into desired uniform widths from asource of suitable sheet material, appropriate mechanism being providedfor selectively varying the rate of advancement of said sheet materialso that bag width will be direct relationship to the size of the articlebeing packaged.

The bags, or packages, are produced or fabricated from a continuouslength of thermoplastic sheet material which is advanced progressivelythrough the machine from a source of supply, the material being severedtransversely to produce bags of predetermined widths wherein the cut orside edges thereof are heat-sealed. Desirably, the sheet material isfolded upon itself along a longitudinal medial line with the freelongitudinal edges disposed in the same forward direction and the foldedlongitudinal edge provides the closed ends or bottoms of fabricatedbag-like containers which are produced from lengths severed transverselyfrom the folded sheet which is advanced from the source of supply andtravels downwardly so as to present the open longitudinal edges towardan operator positioned in front of the machine.

Machines of this character are provided with vertically disposedspreading positioned in the downward path of the folded thermoplasticsheet material for spreading apart the open end thereof a sufficientdistance to permit the convenient insertion of an article to be packagedor bagged and it will be understood that, after the sheet material hasbeen advanced through the machine to a point beneath the spreadingmeans, the sheet material is heat-sealed transversely, at a pointbeneath the spreader, to provide a closed side or leading edge for theinitial bag or container, severance also being accomplished at the pointof seal to remove any surplus wrapping material.

In operation, an article to be packaged is inserted between the opposedlayers of the supply stock and will come to rest upon either the innersurface of the sealed side edge referred to hereabove or a receivingbowl or trough provided for this purpose; advancing the sheet materialto a point Where the article being bagged will have passed beyond thetransverse sealing and severance mechanism, and actuation of suchmechanism at that point, will result in the detachment of a filled andfabricated bag from the end of the folded sheet material, it beingunderstood that the newly created extremity of the supply stock also issealed simultaneously with the severing operation and thus provides aleading edge for each successive bag. As to the fabricated bag, thebottom thereof is closed by reason of the folded longitudinal edge ofthe thermoplastic supply stock and the side edges have been heat-sealed;further, the present invention also contemplates the heat-sealing of thebag mouth, as a unitary operation when the side seal is created, wherebya completely enclosed package is produced.

The sheet material from which such bags are fabricated may be aheat-sealable plastic olefin film, such as the polyethylene,polypropylene, and the like, having transparent characteristics, and thesealing and severing means may be an electrically heated blade wherebythe second side edge and open mouth of a bag length is heatsealedsimultaneously with the severance thereof from the folded supply stock.When a bag length is fed to the sealing and severance mechanism, thefeeding or advancing of the folded sheet material is halted by a timedcontrol to permit accomplishment of sealing and severance, the machinebeing manually adjustable as to bag width and operated intermittentlyfor feeding or advancing a new bag length into position for filling andfor severance of a filled bag length during each cycle of operation.

Machines of the character discussed hereabove are known in the art andheat-sealing has been accomplished heretofore by utilization of a heatedmetallic element, having a knife-like edge, which is brought intoContact with the superposed layers of thermoplastic film, a suitableplaten or the like being provided and against which the layers of filmare engaged at the moment of sealing and severance. Temperature anddwell time are adjusted, or controlled, in strict accordance with thenature and gauge of the thermoplastic film employed. Edge seals areproduced in this manner. Where a fin-type seal is required, having edgesof film extending beyond the line of seal, two spaced seals arerequired, with extreme care being exercised not to burn through thefilm, and severance between the space seals as by use of a cold knife isrequired.

Applicant has discovered that provision of a platen, or other form ofback-up member, is not required and that by utilization of a novel formof sealing blade, and by simultaneously restraining the film againstlateral movement, highly efficient seals may be produced by bringing theheating blade into contact with the film and, Where knife-edge seals aredesired, by continuing movement of the heating blade until it passesthrough the film. Following this novel method of sealing, it is possibleto accomplish tin-type seals by producing a pair of spaced seals andemploying an intermediate knife edge which passes entirely through thelayers of film or which, if desired, may produce a composite perforatedknife-edge seal to permit the production of a multiplicity of unitedpackages which are susceptible of convenient detachment withoutdisturbing package contents.

It is with novel sealing mechanism of this character that the presentinvention is particularly concerned Whereby a transverse end seal andlongitudinal top or bag mouth seal may be produced simultaneously itbeing highly desirable that sharp right angles be created as between thepair of transverse seals and the mouth end closing seal and that surplusmaterial be removed by a sharp and clean severance.

t is a major object of the present invention to provide a combinedbagging machine of the class set forth which is simple in constructionand highly efficient in operation.

It is a further object of the invention to produce a combined baggingmachine of the class set forth having a novel sealing blade forsimultaneously producing side and end seals in a single operation whilepassing through superposed layers of thermoplastic sheet material foldedin surrounding relationship about an article being packaged.

It is a still further object of the present invention to provide novelmechanism in a machine of the class set forth for securely restrainingsuperposed layers of thermoplastic film, disposed in surroundingrelationship about an article being packaged, against lateral movementduring engagement of unrestrained portions thereof by a heated sealingelement.

It is a further object of the present invention to provideinterchangeable and novel sealing mechanism, in a combined bagging andpackaging machine of the class set forth whereby packages may beproduced selectively having either knife-edge or fin-type side seals.

Further objects and advantages of the invention will be readily apparentfrom the following description taken in conjunction with theaccompanying drawings wherein:

FIGURE 1 is a perspective view of a combined bagging and packagingmachine illustrating one embodiment of the present invention;

FIGURE 2 is a fragmentary perspective view, on an enlarged scaie,illustrating the novel sealing and severance mechanism and supportingstructure;

FIGURE 3 is a fragmentary perspective view, also on an enlarged scale,illustrating the sealing and severance blade and the sheet materialrestraining element associated therewith and through which said bladepasses during the sealing and severance operation;

FIGURE 4 is a detail sectional view through the horizontally disposedportion of the sealing and severance blade and associated structureillustrating the sheet material with an article to be packagedpositioned therein, immediately prior to initiation of sealing action;

FIGURE 5 is a detail sectional view similar to FIG- URE 4 andillustrating the film restraining mechanism advanced to engagingposition immediately prior to advancement of the sealing and severanceblade;

FIGURE 6 is a detail sectional view similar to FIG- URE 5 andillustrating the sealing and severance blade at the completion of itsoperative stroke;

FIGURE 7 is a detail sectional view illustrating the mounting andadjustable relationship of the vertically disposed protective guide forthe folded edge of the sheet material;

FIGURE 8 is a fragmentary perspective view of one of the filmrestraining or gripping jaws;

FIGURE 9 is a fragmentary plan view illustrating mechanism forcontrolling movement in unison of the opposed sheet material restrainingor gripping jaws;

FIGURE 10 is a plan view of the sealed and severed package produced inaccordance with the present invention;

FIGURE 11 is a fragmentary perspective view of a modified form ofsealing and severance blade whereby fin-type seals may be produced;

FIGURE 12 is a detail sectional view, comparable to FIGURE 4illustrative of the modified film restraining elements required inconnection with utilization of the sealing and severance bladeillustrated in FIGURE 11;

FIGURE 13 is a plan view of a sealed and severed package with fin-typeseals; and

FIGURE 14 is a fragmentary plan view illustrative of a plurality offin-type bags prior to detachment as between adjacent bags.

With continued reference to the drawings, as illustrated moreparticularly in FIGURES 1 and 2 thereof, the novel bagging and packagingmachine of the present invention comprises a supporting base havingvertically disposed standards or posts 21 mounted thereupon. A Worksurface or table 22 is supported upon the standards 21, at a desirablyconvenient level, for receiving a supply of articles to be bagged orpackaged. This work surface may be provided with rear and end retainingwalls or flanges and, for convenience of operation, may be placed at thelight of the machine or at the left thereof, for right-handed andleft-handed operators, respectively, and articles to be packaged may bestacked or otherwise positioned upon the table for ready accessibility.It should be understood that while this work surface, or table, has beenillustrated and described as a unitary part of the device, this is by nomeans essential since articles to be packaged may be supported otherwiseor presented to the operator as may be desired.

A suitable housing, indicated generally at 23 is mounted upon uprightsor posts 24 and 25, which extend above the work table, for supporting asupply of thermoplastic sheet wrapping material 26 together withmechanism whereby such material may be advanced or fed through themachine in the performance of bagging and packaging functions.

This sheet wrapping material 26 is provided in the form of a roll 27carried upon a shaft or reel appropriately journalled within the housing23, and may be of any suitable thermoplastic material, such as one ofthe polyolefins including polyethylene, polypropylene, and the like, andis folded along a longitudinal medial line 28 to dispose the twojuxtaposed halves 29 and 30 thereof in the same general direction forproviding one longitudinal closed end along the medial line 28 and anopen end between the free longitudinal edges of the half portions 2? and30, thereby creating a continuous pocket which extends throughout theentire length of the folded sheet.

From the supply roll 27 the sheet or film 25 passes over a suitablefestooning device (not shown) supported within the housing 23 and isthreaded or fed through the machine up and over a feed or drive roller31. Suitable braking and other mechanism, as is well known in this art,is provided for controlling the intermittent advancement of the foldedsupply sheet or film during operation of the machine, the festooningdevice functioning automatically to obviate any possibility of slackduring such intermittent operation.

Selectively adjustable means is provided for intermittently advancing orfeeding uniform and predetermined lengths of sheet material through themachine and such means may include a horizontally disposed rod 32 havingoperative connection with rack and pinion mechanism 33 and 34 andprovided with a control knob 35 whereby the length of sheet materialbeing advanced may be adjusted conveniently, and closely controlled, instrict accordance with the size of the article being packaged. Ifdesired, hydraulic means indicated at 36 may be provided for returningthe rack 33 to normal position, a oneway clutch (or comparable device)being associated with pinion 34- which may have direct connection withthe feed or drive roller 31.

As the sheet material 26 is fed downwardly, beyond the feed roller 31,the juxtaposed halves thereof 29 and 3d are separated by means ofsuitable spreader mechanism disposed within the path of movement. Thisspreader device may be in the form of horizontally mounted rods or thelike 37 and 38 which are adjustably secured to the bracket 39 carried bythe post 24, desirably, one of these rods terminates in a verticallydisposed depending portion 40 which may be adjusted so as to engage withthe inner surface of the medial fold 28 of the sheet material. Further,to avoid any possibility that the juxtaposed halves 29 and 30 of thesheet material may cling together by reason of static electricity, orthe like, a suitable static eliminator (not shown) may be provided as iswell known in this art.

To support the folded inner extremity or edge 28 of the sheet wrappingmaterial, and prevent possibility of damage thereto as by forcefulcontact with an article being packaged or the like, a verticallydisposed V-shaped guide or back-up plate 41 is provided and this plateis supported by an arm 42 (FIGURE 7) carried by a sleeve 43 or the likewhich is slidably adjustable upon the bar 44 mounted between theuprights 24 and 25. It will be obvious that the back-up plate 41 andspreader mechanism or arms 37 and 38 are readily adjustable inaccordance with the width of the folded sheet material 26.

A horizotally disposed sealing and serving unit is positioned within themachine below the level of the spreader mechanism and, as an initialstep in connection with the operation of the novel machine of thepresent invention, a transverse seal S (FIGURE 4) is provided adjacentthe leading extremity of the sheet material after it has been advancedto packaging position beyond the lower extremity of the dependingportion 49 of the spreader means. This transverse seal, which isaccomplished by subjecting the end of the folded supply sheet to theaction of the novel transverse sealing and severing unit (to bedescribed hereafter), becomes one side edge of the first bag orpackaging unit and each subsequent sealing and severance operationprovides simultaneously the mouth closing seals as well as the otherside edge seal of said bag and also the first side edge seal of the nextsuccessive packaging unit.

As illustrated more particularly in FEGURES 2 through 6 of the drawings,the novel horizontally disposed sealing and severance mechanism orunitary assembly is mounted within a substantially rectangular chassisor frame indicated generally at 45 and which includes side rails 45 and47 and end members 43 and 49. Opposed beams or bars 5@ are supportedbetween the end memers 43 and 49 and the extremities of one of anopposed transversely disposed pair of gripping or restraining jaws 51and 52 is secured to said beams for reciprocatory movement.

The jaw 51 (FIGURES 3 and 4) includes a pair of horizontally disposedbars 53, spaced as indicated at 54, and a depending pair of verticallydisposed spaced bars 55 and the heated sealing and severance element 56,which is generally T-shaped and will be described more fully hereafter,passes through said space when scaling is accomplished. The jaw 52(FIGURES 4- and 8) is provided with a complementarily conformed face andcomprises horizontally disposed bars 57, spaced as at 58 and carried bythe transverse member 55, and vertically disposed spaced bars 6%.Complementary halves 61 of a trough or receiving bowl are mounted uponthe opposed faces of the bars 53 and 57, as shown more particularly inFIGURES 4, 5 and 6, and as the trough is closed for the reception of anitem to be packaged, the juxtaposed halves 3t and 29 of the folded sheetmaterial are re strained between the opposed faces of the bars 53 and 57of the jaws 51 and 52.

As shown more particularly in FIGURE 3 of the drawings, the sealing andseverance element 56, which may be metallic or of any other suitablematerial, is generally T- shaped in configuration and includes ahorizontal cross bar or head portion 62 for producing the side seal anda vertical off-set stern portion 53 for producing the bag mouth seal. Toprovide for a sharp right angle between the side and mouth seals, whichare produced simultaneously, the projecting portion or extremity 62a isprovided on the cross bar 62, it being understood that this projectingportion severs through surplus sheet material which is removed as thebag mouth is sealed. Through such structure a sharp right angle isprovided at the juncture of the side and mouth seals thereby insuringthe efiicacy thereof and eliminating serious deficiency present in priorart practices where such juncture has a tendency to provide a weakenedarea in the sealed package.

Desirably the leading or sealing face of the sealing and severanceelement is provided with a sharp, knifelike edge which penetratesthrough the juxtaposed halves of thermoplastic material and, in suchpassage, produces a cleanly welded edge on the bag or package beingcompleted as well as providing a similar sealed side edge for the nextsuccessive bag or container. Electrical means, not shown and withsuitable thermostatic control as is well known in this art, is providedfor maintaining the sealing and severance element at an appropriatesealing temperature in accordance with the specific characteristics ofthe thermoplastic material employed. Further, where such a sealingelement is required only to pass through (by melting) thermoplasticfilm, and does not contact platens or the like which are perforcemaintained at substantially lower temperatures, the sealing lade is notsubjected to intermittent cooling influences during operation of themachine and constantly uniform 6 seals may be produced with greaterspeeds of machine operation than has been possible heretofore.

Suitable means is provided for actuating the restraining jaws 51 and 52and the sealing and severance element 56. Such means may be hydraulicand includes a fluid cylinder 64 mounted adjacent the end bar 49 of theframe 45 and having a piston 65 fixedly connected to the jaw 52. Thus,upon advancement of the piston 65 the jaw 52, carrying therewith onehalf of the receiving trough, will be moved toward restraining positionand means (such as rack and pinion, or the like, as illustrated in FIG-URE 9) is provided for simultaneosuly imparting reverse motion to thecompanion jaw 51, carrying therewith the complementary half of thereceiving trough, whereby these jaws may move in unison toward and awayfrom each other.

In like manner a fluid cylinder 66 is mounted upon the end bar or member48 of the frame 45 and the piston 67 of this hydraulic cylinder isfixedly connected to the sealing and severance element 56. Thus, uponadvancement of the piston 67, in timed relation to the restraining ofthe juxtaposed halves of sheet material between the jaws 51 and 52, thesealing and severance element 56 will be advanced or projected throughthe space Se in the jaw 51 so as to engage and penetrate the sheetmaterial whereby side edge and mouth sealing and severance is completed.

In connection with the advancement of the sealing and severage mechanismthrough the film, at which time melting and sealing is accomplished, ithas been found highly advantageous to control the rate of movement ofthe sealing and severance blade whereby at the completion of the stroke,and immediately prior thereto as at the moment of contact with thejuxtaposed layers of sheet material, the blade travels at asubstantially reduced rate of speed in comparison with the initial andreturn speed of movement thereof. Suitable mechanism is provided forthis purpose, thereby insuring that each severed edge will be completelysealed, the strength of such seals being many times greater than thetear strength of the sheet material per se.

One form of mechanism for controlling the rate of movement of thesealing blade may include a rod or the like 67a having an extremitysecured to an upstanding flange 67b mounted upon the piston 67. This rodpasses through an aperture in a companion flange 68!) carried by thefluid cylinder 68 and is provided with a threaded or otherwiseadjustable cap or the like 670, a coil spring 67a being interposedbetween the flange 68b and the cap 670. It will be obvious that as thepiston nears the end of its stroke the spring 67d is under constantlyincreasing pressure, this resulting in the slowing down or retarding or"the forward movement of the sealing element.

The complete sequence of sealing and severance is illustrated in FIGURES4, 5 and 6 of the drawings in step-by-step operation. In FIGURE 4, withan initial side seal S provided and a cylindrical article A to bepackaged resting thereupon, the jaws 51 and 52 are in open or retractedposition. In FIGURE 5, advancement of the piston 55 of the fluidcylinder 64 has closed the restraining or gripping jaws 51 and 52against the halves 29 and 30 of the folded sheet material and also hasbrought together the complementary halves 61 of the receiving trough orbowl. In FIGURE 6, a new article A has been positioned within thereceiving trough and advancement of the piston s? of the fluid cylinder66 has projected the sealing blade 56 through the space 54 provided inthe jaw 51 and into the space 58 of the jaw 52 whereby sealing andseverance has been completed and a completely sealed package will bedelivered to an appropriate area or receptacle upon retraction of therestraining or gripping jaws.

The bagging and packaging machine may have any suitable automatic ormanual control, as indicated by the start-stop buttons 63 and 69(FIGURE 1) or, if desired, a foot control (not shown) may be provided.

There has been illustrated somewhat diagrammatically in FIGURE 9 of thedrawings one mechanical arrangement for moving the jaws 51 and 52 towardand away from each other in unison. As shown, a rack 70 is secured tothe inner surface of each beam member 50 and a complementary rack 71 issecured in spaced parallel relationship to the adjacent extremities ofthe jaw 52. A pinion '72 mounted upon a suitable stub shaft or the likeis interposed between each pair of racks 7 and 71 and meshes therewith.With this arrangement of elements, as jaw 52 is moved under theinfluence of the piston 65 toward closed or film restraining position,the beams '0 are moved in the opposite direction carrying therewith theopposed restraining or gripping jaw 51. Thus, the opposed jaws move inunison at all times whether toward or away from each other.

A completely sealed package P has been illustrated in FIGURE 10 of thedrawings having knife-edge side seals S and S1 and a mouth seal M,article A being enclosed therein. It will be noted that side edge seal Salso is created on the leading edge of the folded sheet material 26 andthat the surplus material SM has been notched as indicated at N by theextending portion 62a of the cross bar 62 of the sealing element 56,thus creating a sharply right-angular sealed corner at the intersectionof the two seals. To dispose continuously of such surplus material, thismay be directed into a vent tube 73 (FIGURE 1) having vacuum meansassociated therewith.

Where it is desired to avoid contacting the film under restraint bymetallic surfaces, the opposed faces of the jaws 51 and 52 may beprovided with protective coatings or inserts indicated respectively at51a and 52a (FIG- URES 3, 8 and 12).

There has been illustrated in FIGURES l1 and 12 of the drawings amodified form of sealing element whereby fin-type seals may be produced.As shown, this form of sealing and severance element 74, which may bemetallie or of any other suitable material, is generally T-shaped inconfiguration and includes a horizontal cross-bar or head portion 75 forproducing the side edge seal and a vertically disposed offset stemportion 76 for producing the bag mouth seal. The head portion 75 isprovided with a pair of spaced and relatively narrow bar-type sealingedges 77 and with a centrally located sealing and severance knife-typeblade 78. In distinction, the bag mouth sealing is accomplished by asingle knife-type blade 79.

In operation, when the restraining or gripping jaws 51 and 52 are closedagainst the folded sheet material, the spaced sealing edges 77 come intocontact with the juxtaposed layers of film, the jaw 52 being providedwith a platen or the like 84) (produced from suitable material such asTeflon, or the like) and simultaneously therewith the centrally locatedseverance blade 78 enters into a notch 81 in the platen 80 wherebycomplete severance is accomplished. Thus, each bag edge is provided witha seal S2 (FIGURE 13) parallel to but spaced from the severed edges Sand S1.

If desired, the severance blade 78 may have a sealing edge in the formof closely spaced teeth 78a in which event instead of a line of completeseverance being accomplished, a row of perforations S3 (FIGURE 14) willbe provided whereby a plurality of attached and completely sealedpackages will be produced. Each of these being subject to readydetachment.

The package P1, illustrated in FIGURE 13 of the drawings, has a bar-typeseal S2 located adjacent the side edge seals S and 51 whereby fin-typeside seals have been created. The bag mouth seal M is illustrated as asimple knife-edge seal. it will be understood however, that fintypeseals also may be provided at the bag mouth with particular facility.

The packages P2, illustrated fragmentarily in FIGURE 14 of the drawings,have bar-type side edge seals S2 and a perforated partially sealed edgeS3 therebetween, it being understood that the edges of each aperture inthe line of 8 perforation has been heat-sealed when the teeth 78apenetrated the juxtaposed layers. Thus, the sealed packages illustratedin FIGURES 13 and 14 are not only tin-type but have dual seals along theedges thereof.

With the novel bagging and packaging machine of the present invention,adjustment as tobag size (whether epth or width) may be accomplishedwith particular facility and, in the event that open end packages arerequired, the sealing and severance element may be removed and a singlehorizontally disposed knife-edge sealer Substituted. In this manner theinventive concept may he carried into practice, sealing and severance ofjuxtaposed layers of film being accomplished with particular efficiencyand with the sheet material unsupported at the point of contact with thesealin g element.

It will be understood that the invention is not considered limited bythat which is shown in the drawings and described in the specificationand reference therefore is had to the claims for summaries of theessentials of the invention, novel features of construction and novelcombination of parts for all of which protection is desired.

What is claimed is:

1. A bagging and packaging machine comprising adjustable means forintermittently advancing downwardly predetermined length of foldedthermoplastic sheet Wrapping material having an open side, a spreaderfor spreading the open side of said sheet wrapping material, first andsecond reciprocable gripping jaws mounted transversely beneath thespreader and movable in unison toward and away from each other torestrain the folded sheet wrapping material therebetween, said firstgripping jaw having a recess extending therethrough and the opposed faceof said second gripping jaw being provided with a complementarily shapedand aligned recess, a transversely mounted reciprocable heated sealingelement for sealing and severing said folded sheet wrapping material,said sealing element having a forwardly directed edge and being movablethrough the recess in said first gripping jaw independently of and intimed relation to the closing of said gripping jaws to a position wheresaid forwardly directed edge penetrates the layers of sheet wrappingmaterial restrained between said gripping jaws and enters into therecess in the face of said second gripping jaw providing a sealed andsevered edge along the path of penetration, and means for reducing thespeed of movement of said heated sealing element immediately prior topenetration through the restrained sheet wrapping material.

2. Sealing and severance mechanism for thermoplastic sheet materialcomprising first and second reciprocable gripping jaws movable towardand away from each other to intermittently restrain at least twojuxtaposed layers of such sheet material therebetween, said firstgripping jaw having a recess extending therethrough and the opposed faceof said second gripping jaw being provided with a complementarily shapedand aligned recess, a transversely disposed heated sealing element forsealing and severing said juxtaposed layers of sheet material, saidsealing element having a forwardly directed edge, means for moving saidsealing element through the recess in said first gripping jawindependently of and in timed relation to the closing of said grippingjaws to a position where said forwardly directed edge penetrates thelayers of sheet material restrained between said gripping jaws andenters into the recess in the face of said second gripping jaw providinga sealed and severed edge along the path of penetration, and means forreducing the speed of movement of said heated sealing elementimmediately prior to penetration through the restrained sheet material.

3. Sealing and severance mechanism as set forth in claim 2 wherein theleading edge of said heated sealing element is of T-shaped configurationincluding a horizontally disposed cross bar and a vertically disposedoffset stem portion and the recesses in said gripping jaws arofcomplementary configuration.

4. Sealing and severance mechanism as set forth in claim 3 wherein saidcross bar is provided with a pair of spaced and relatively narrowbar-like sealing surfaces With a centrally located knife-like sealingand severance blade of greater depth than said bar-like sealing surfacesprojecting therebetween.

5. Sealing and severance mechanism as set forth in claim 4 wherein theleading edge of said knife-like sealing and severance blade isconstituted by a plurality of relatively narrow and uniformly spacedteeth.

References Cited UNITED STATES PATENTS Smith 53-182 Bracey 53182 Newellet a1. 53-182 Cochrane 53182 Joa 53-182 Grevich et a1. 53182 10GRANVILLE Y. CUSTER, JR., Primary Examiner.

1. A BAGGING AND PACKAGING MACHINE COMPRISING ADJUSTABLE MEANS FORINTERMITTENTLY ADVANCING DOWNWARDLY A PREDETERMINED LENGTH OF FOLDEDTHERMOPLASTIC SHEET WRAPPING MATERIAL HAVING AN OPEN SIDE, A SPREADERFOR SPREADING THE OPEN SIDE OF SAID SHEET WRAPPING MATERIAL, FIRST ANDSECOND RECIPROCABLE GRIPPING JAWS MOUNTED TRANSVERSELY BENEATH THESPREADER AND MOVABLE IN UNISON TOWARD AND AWAY FROM EACH OTHER TORESTRAIN THE FOLDED SHEET WRAPPING MATERIAL THEREBETWEEN, SAID FIRSTGRIPPING JAW HAVING A RECESS EXTENDING THERETHROUGH AND THE OPPOSED FACEOF SAID SECOND GRIPPING JAW BEING PROVIDED WITH A COMPLEMENTARILY SHAPEDAND ALIGNED RECESS, A TRANSVERSELY MOUNTED RECIPROCABLE HEATED SEALINGELEMENT FOR SEALING AND SEVERING SAID FOLDED SHEET WRAPPING MATERIAL,SAID SEALING ELEMENT HAVING A FORWARDLY DIRECTED EDGE AND BEING MOVABLETHROUGH THE RECESS IN SAID FIRST GRIPPING JAW INDEPENDENTLY OF AND INTIMED RELATION TO THE CLOSING OF SAID GRIPPING JAWS TO A POSITION WHERESAID FORWARDLY DIRECTED EDGE PENETRATES THE LAYERS OF SHEET WRAPPINGMATERIAL RESTRAINED BETWEEN SAID GRIPPING JAWS AND ENTERS INTO THERECESS IN THE FACE OF SAID SECOND GRIPPING JAW PROVIDING A SEALED ANDSEVERED EDGE ALONG THE PATH OF PENETRATION, AND MEANS FOR REDUCING THESPEED OF MOVEMENT OF SAID HEATED SEALING ELEMENT IMMEDIATELY PRIOR TOPENETRATION THROUGH THE RESTRAINED SHEET WRAPPING MATERIAL.